This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. Primary support for the subproject and the subproject's principal investigator may have been provided by other sources, including other NIH sources. The Total Cost listed for the subproject likely represents the estimated amount of Center infrastructure utilized by the subproject, not direct funding provided by the NCRR grant to the subproject or subproject staff. This proposed pilot project seeks to apply metabolic approaches to uncover new roles (and action mechanisms) for factors that may balance progenitor cell apportioning towards bone vs fat formation. One factor is a transcriptional repressor within the Snail family. A second is a co-factor for insulin-like growth factor (IGF) as IGF-binding protein-2 (IGF-BP2). As preliminary results, the conditional knockout of each (as accomplished by Drs Gridley and Rosen) appears to markedly affect adipogenesis and bone morphogenesis. Both global, and mechanistic insight into IGF-BP2 and Snail actions stand to be advanced through metabolic monitoring.